<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        body {
            font-family: Verdana, sans-serif;
            margin: 0;
        }

        * {
            box-sizing: border-box;
        }

        .row>.column {
            padding: 0 8px;
        }

        .row:after {
            content: "";
            display: table;
            clear: both;
        }

        .column {
            float: left;
            width: 25%;
        }

        /* The Modal (background) */

        .modal {
            display: none;
            position: fixed;
            z-index: 1;
            padding-top: 100px;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            overflow: auto;
            background-color: black;
        }

        /* Modal Content */

        .modal-content {
            position: relative;
            background-color: #fefefe;
            margin: auto;
            padding: 0;
            width: 90%;
            max-width: 1200px;
        }

        /* The Close Button */

        .close {
            color: white;
            position: absolute;
            top: 10px;
            right: 25px;
            font-size: 35px;
            font-weight: bold;
        }

        .close:hover,
        .close:focus {
            color: #999;
            text-decoration: none;
            cursor: pointer;
        }

        .mySlides {
            display: none;
        }

        .cursor {
            cursor: pointer
        }

        /* Next & previous buttons */

        .prev,
        .next {
            cursor: pointer;
            position: absolute;
            top: 50%;
            width: auto;
            padding: 16px;
            margin-top: -50px;
            color: white;
            font-weight: bold;
            font-size: 20px;
            transition: 0.6s ease;
            border-radius: 0 3px 3px 0;
            user-select: none;
            -webkit-user-select: none;
        }

        /* Position the "next button" to the right */

        .next {
            right: 0;
            border-radius: 3px 0 0 3px;
        }

        /* On hover, add a black background color with a little bit see-through */

        .prev:hover,
        .next:hover {
            background-color: rgba(0, 0, 0, 0.8);
        }

        /* Number text (1/3 etc) */

        .numbertext {
            color: #f2f2f2;
            font-size: 12px;
            padding: 8px 12px;
            position: absolute;
            top: 0;
        }

        img {
            margin-bottom: -4px;
        }

        .caption-container {
            text-align: center;
            background-color: black;
            padding: 2px 16px;
            color: white;
        }

        .demo {
            opacity: 0.6;
        }

        .active,
        .demo:hover {
            opacity: 1;
        }

        img.hover-shadow {
            transition: 0.3s
        }

        .hover-shadow:hover {
            box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19)
        }
    </style>
</head>

<body>
    <h2 style="text-align:center">Lightbox</h2>

    <div class="row">
        <div class="column">
            <img src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
        </div>
        <div class="column">
            <img src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
        </div>
        <div class="column">
            <img src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
        </div>
        <div class="column">
            <img src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
        </div>
    </div>

    <div id="myModal" class="modal">
        <span class="close cursor" onclick="closeModal()">&times;</span>
        <div class="modal-content">

            <div class="mySlides">
                <div class="numbertext">1 / 4</div>
                <img src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%">
            </div>

            <div class="mySlides">
                <div class="numbertext">2 / 4</div>
                <img src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%">
            </div>

            <div class="mySlides">
                <div class="numbertext">3 / 4</div>
                <img src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%">
            </div>

            <div class="mySlides">
                <div class="numbertext">4 / 4</div>
                <img src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%">
            </div>

            <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
            <a class="next" onclick="plusSlides(1)">&#10095;</a>

            <div class="caption-container">
                <p id="caption"></p>
            </div>


            <div class="column">
                <img class="demo cursor" src="http://static.runoob.com/images/demo/demo1.jpg" style="width:100%" onclick="currentSlide(1)"
                    alt="Nature and sunrise">
            </div>
            <div class="column">
                <img class="demo cursor" src="http://static.runoob.com/images/demo/demo2.jpg" style="width:100%" onclick="currentSlide(2)"
                    alt="Trolltunga, Norway">
            </div>
            <div class="column">
                <img class="demo cursor" src="http://static.runoob.com/images/demo/demo3.jpg" style="width:100%" onclick="currentSlide(3)"
                    alt="Mountains and fjords">
            </div>
            <div class="column">
                <img class="demo cursor" src="http://static.runoob.com/images/demo/demo4.jpg" style="width:100%" onclick="currentSlide(4)"
                    alt="Northern Lights">
            </div>
        </div>
    </div>
</body>
<script>
    function openModal() {
        document.getElementById('myModal').style.display = "block";
    }

    function closeModal() {
        document.getElementById('myModal').style.display = "none";
    }

    var slideIndex = 1;
    showSlides(slideIndex);

    function plusSlides(n) {
        showSlides(slideIndex += n);
    }

    function currentSlide(n) {
        showSlides(slideIndex = n);
    }

    function showSlides(n) {
        var i;
        var slides = document.getElementsByClassName("mySlides");
        var dots = document.getElementsByClassName("demo");
        var captionText = document.getElementById("caption");
        if (n > slides.length) { slideIndex = 1 }
        if (n < 1) { slideIndex = slides.length }
        for (i = 0; i < slides.length; i++) {
            slides[i].style.display = "none";
        }
        for (i = 0; i < dots.length; i++) {
            dots[i].className = dots[i].className.replace(" active", "");
        }
        slides[slideIndex - 1].style.display = "block";
        dots[slideIndex - 1].className += " active";
        captionText.innerHTML = dots[slideIndex - 1].alt;
    }
</script>

</html>